This invention relates to a pallet made of a synthetic resin wherein slip preventing members are provided for the deck board of the pallet.
Synthetic resin pallets are now widely used in many applications, because their water absorption is small, can be cleaned readily and sanitary, can be produced by mass production technique to have a stable quality and definite dimensions and shape and because they are free from any splinter or hangnail inherent to pallets made of wood. However, synthetic resin pallets are not advantageous in that they are slippery thus causing rupture or damage not only to the pallets themselves but also goods mounted thereon.
For example, when conveying synthetic resin pallets by a chain or roller conveyor or a fork lift they are liable to slip on such conveyors so that the stability of stacked pallets is lost. Especially when pallets are lowered along inclined conveyors installed in warehouses or the like, the descending speed of the pallets increases acceleratedly. In such a case, it is difficult to control the speed of the pallets with the result that they collide with each other. Moreover, when the pallets are stopped, the goods becomes unstable due to moment of inertia and often fall down.
To prevent such slippage it has been the practice to form irregularities on the deck board at the time of moulding a pallet, or to form opening in the deck board after moulding for inserting rubber projections. With such slip preventing members, it has been difficult to effectively prevent slippage according to the type and shape of the goods and the type, shape and method of operation of the conveyor system.
Alternatively, a flat rubber sheet having a large coefficient of friction was bonded to the pallet. However, when the pallet is made of a polyolefin resin, for example, the bonding property is poor so that the rubber sheet tends to peel off. Prevention of slippage involves problems that can not be solved by the coefficient of friction alone. More particularly, if the coefficient of friction were too high, when the pallets are subjected to a shock the goods can not slide so that the stacked goods would fall down as a column.